Whatever model of .44 mag you're considering...ideally you should try and shoot one first, if you haven't, just to make sure its what you really want...

The heavier guns ...with longer barrels...mean less recoil / weight is your friend in this recoil issue. But shooting a lower velocity round ..in .44 spl..and the lightest bullet you can find at the slowest velocity is the type of round you'll need for her to get used to this gun.
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You should buy what you want....but hopefully you've at least considered .357 mag's as well...lots of nice guns in .357 mag as well..and a lot "tamer" to shoot ( in .38 spl's )...